Exhaust systems usually includes an exhaust line that carries the exhaust away from the internal combustion engine. In certain applications, it may be necessary to inject fuel into the exhaust line in addition. For example, the injection of such a secondary fuel upstream from an oxidation catalytic converter can greatly increase the exhaust temperature, e.g., to trigger regeneration of a particulate filter. For injection of fuel into the exhaust line, the exhaust system may be equipped with at least one fuel injector which is mounted on the exhaust line via a suitable mounting device. Essentially such a fuel injector may be one that is known per se for injection of fuel into the combustion chambers of an internal combustion engine.
It is problematical here that relatively high temperatures may occur in and/or on the exhaust line but at the same time the fuel injector must not exceed a certain maximum allowed operating temperature. It is fundamentally possible to actively cool the fuel injector to thereby prevent overheating of the fuel injector.
The present invention is concerned with the problem of providing an improved embodiment for an exhaust system of the type defined in the preamble in which the fuel injector in particular has improved protection from overheating.